JPH0445184Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a tape cassette suitable for use in recording digital signals, such as PCM signals.

[Summary of the idea]

The present invention provides a tape cassette in which a brake member for regulating rotation of a reel hub is slid along grooves provided on the cassette case side with leg parts formed on both sides of the brake member. By making the outer side biased toward the outer edge of the groove of the cassette half, warping during molding caused by the basic shape of the brake member can be canceled and the brake member can interfere with the tape wound around the reel hub. This has resulted in a tape cassette that allows smooth tape running without any problems.

[Conventional technology]

BACKGROUND ART Currently, a PCM recording and reproducing apparatus has been proposed that converts an analog signal such as an acoustic signal into a digital signal, such as a PCM signal, and records (or reproduces) the converted signal on a magnetic tape. Some PCM recording and reproducing apparatuses use a rotating head to achieve a relatively high recording density. Using this rotating head
In a PCM recording/reproducing apparatus, during recording or reproduction, a magnetic tape is pulled out from a tape cassette and loaded onto a rotating drum provided with a rotating head, and then recording or reproduction is performed.

By the way, in the tape cassette into which this magnetic tape is loaded, if a finger touches the magnetic tape and oil or fat or dust gets on it, a dropout occurs in the playback signal, so it is important to avoid touching the magnetic tape with fingers or getting dust. It is necessary to seal the magnetic tape as tightly as possible to prevent this. Also, a space is required for inserting a guide system so that the magnetic tape can be pulled out from the tape cassette during recording or reproduction.

For this reason, tape cassettes as shown in FIGS. 7 to 15 have been proposed. That is, Figures 7 and 8
In the figure, reference numeral 1 indicates a cassette case, and this cassette case 1 is composed of a pair of upper half 2 and lower half 3 that are joined together by screws. 2
A is a transparent window plate provided on the upper surface of the upper half 2. Reference numerals 4a and 4b denote a pair of reel hubs that are housed in the cassette case 1 and are rotatably fitted loosely into a pair of reel shaft insertion holes 5a and 5b provided at predetermined positions in the lower half 3; A magnetic tape 6 is wound around 4a and 4b. Reference numerals 7a and 7b are tape guide columns provided near the left and right side walls facing the front surface, respectively, and the magnetic tape 6 is wound around these tape guide columns 7a and 7b to maintain a predetermined position on the front surface. It will be made runnable. 3a is the tape guide column 7a
The lower half 3 on the back side of the magnetic tape 6 wound on the magnetic tape 6 and 7b is a notch cut out in a substantially rectangular shape over a predetermined width. A guide system for pulling out the magnetic tape is inserted.

Reference numeral 8 denotes a front cover that is pivotally supported by arm portions 8a and 8b on both sides so as to be able to rotate toward the front side of the cassette case 1, and the front side of the cassette case 1 is opened and closed by this front cover 8. Ru.

Reference numeral 9 denotes a slider having a substantially U-shaped cross section and facing the lower surface and left and right side walls of the lower half 3 and sliding in the front-rear direction. Further, 9a and 9b are inserted into the reel shaft insertion holes 5a and 5b, respectively, when the slider 9 is slid backward to open the notch 3a.
This is a reel shaft insertion hole drilled in the slider 9 in correspondence with the reel shaft insertion hole. Note that 10a and 10b are positioning holes provided on the lower surface side corresponding to the tape guide columns 7a and 7b, respectively.

Further, when the slider 9 is slid forward with the front cover 8 closed, its reel shaft insertion holes 9a and 9b are in a state where they do not correspond to the reel shaft insertion holes 5a and 5b of the cassette case 1. At the same time, the notch 3a of the cassette case 1 and the positioning hole 10a
and 10b are closed, and the inside of the cassette case 1 is almost completely sealed, thereby preventing dust from adhering to the tape 6 and preventing fingers or the like from coming into contact with the tape 6.

In this state, the side plates 9c and 9 of the slider 9
d is located below the arm portions 8a and 8b of the front cover 8, and the upper edge of the side plate portions 9c and 9d of the slider 9 abuts the lower edge of the arm portions 8a and 8b of the front cover 8, whereby the front The lid 8 is locked unrotatably to prevent the front lid 8 from being opened inadvertently during storage.

In this state, the tape reels 4a and 4 stored in the hermetically sealed cassette case 1 are
A reel brake member 11 is provided within the cassette case 1 to prevent the tape 6 from becoming slack due to unexpected rotation of the tape 6 due to vibration or the like.

The brake member 11 is formed into a substantially U-shaped cross section by a plate-shaped portion 11a along the inner surface of the upper half 2, and leg portions 11b and 11c hanging below both left and right ends of the plate-shaped portion 11a. In this case, the plate-like part 1
Brake protrusions 11d and 11e are provided on the rear side of 1a corresponding to reel hubs 4a and 4b, respectively. Incidentally, ratchet wheels 4c and 4d are provided on the outer periphery of the upper half 2 side of the reel hubs 4a and 4b in correspondence with the brake protrusions 11d and 11e, respectively.

Moreover, the leg portions 11b and 1 of this brake member 11
1c, guide grooves 12 and 13 are formed in the bottom part of the lower half 3 along the left and right side walls, and the legs 11b and 11c are formed in the grooves 12 and 13.
are engaged with each other, and the brake member 11 is slid in the front-rear direction.

Further, a spring locking portion 11f is provided at the center of the plate-like portion 11a of the brake member 11, and operating elements 11g and 11h are provided at the ends of the leg portions 11b and 11c, respectively. In this case, a spring 14 for biasing the reel brake body 11 is locked in the spring locking portion 11f, and the free end of the spring 14 presses the shielding wall 3b of the upper half 2, so that the bias of the spring 14 is The force causes the brake member 11 to slide rearward, and the protrusions 11d, 1
1e is the pawl wheel 4c, 4d of the reel hub 4a, 4b
The reel hubs 4a and 4b are locked so that they cannot rotate. Further, when the brake member 11 is placed in the cassette case 1, the operating elements 11g,
11h projects a predetermined amount to the outside of the front end of the side wall through the operator insertion hole 15 of the lower half 3, and when the front cover 8 is rotated upward, this protruding operator 11g and 11h are pressed by the ends of the arm portions 8a and 8b of the front cover 8, the brake member 11 is slid forward along the grooves 12 and 13 against the biasing force of the spring 14, and the brake protrusion 1
1d and 11e are separated from the ratchet wheels of the reel hubs 4a and 4b, allowing the reel hubs 4a and 4b to rotate.

[Problem that the invention attempts to solve]

Due to its basic shape, it is difficult to mold the brake member 11 of the conventional tape cassette constructed in this way into a perfect U-shape.In other words, due to the effects of heat shrinkage after molding, etc. shaped part 11a
is bent downward, and the legs 11b and 11c are bent inward, that is, a so-called inwardly curved shape.

Therefore, when assembling this brake member 11, the legs 11b and 11c, which are bent inwardly with respect to the plate-shaped part 11a, are pushed outward and spread apart.
Its inner side is the inner edge 1 of the grooves 12 and 13, respectively.
2a and 13a so as to be in contact with each other.

However, when the legs 11b and 11c of the brake member 11 are pushed outward in this way,
Along with this, the plate-like part 11a is further bent downward, and the space between the plate-like part 11a and the bottom surface of the lower half 3 becomes narrower. The load torque of the tape 6 increases as a result of interference with the tape 6 wound around the brake member 11, which impedes smooth running and increases friction loss of the brake member 11.

The present invention has been devised in view of these points, and attempts to solve the above-mentioned problems by considering the relationship between the hub brake member and the groove on the cassette case side.

[Means for solving problems]

In order to achieve the above-mentioned object, the present invention has a U-shaped cross section consisting of a plate-like part 21a having a pair of protrusions 21d and 21e that engage with the reel hubs 4a and 4b, and leg parts 21b and 21c provided on both sides of the plate-like part 21a. The tape has a brake member 21, and the lower half 3 of the upper and lower halves 2 and 3 in which the brake member 21 is housed is provided with a pair of grooves 12 and 13 in which the legs 21b and 21c of the brake member 21 slide. In the cassette, the brake member 21 is arranged so that the distance A between the lower outer edges of the legs 21b and 21c on both sides is approximately equal to the distance B between the outer edges of the pair of grooves 12 and 13 provided in the lower half 3. The legs 21b and 21 of the brake member 12 are formed to be slightly larger.
The outer sides of the grooves c are biased to the outer edges of the pair of grooves 12 and 13, respectively.

[Effect]

In this way, the outer parts of the legs 21b and 21c of the brake member 21 are connected to the outer edges 12 of the grooves 12 and 13.
By being biased toward b and 13b, the so-called inward warpage of the plate-like portion 21a of the brake member 21 is canceled, and therefore the brake member 21 is biased toward the tape 6 wound around the reel hubs 4a and 4b. This results in stable tape running without interference.

〔Example〕

Embodiments of the present invention will be described below with reference to FIGS. 1 to 6. In addition, the above-mentioned figures 7 to 15
The same reference numerals are given to the members corresponding to those in the figures, and the explanation thereof will be omitted.

First, in the first embodiment shown in FIGS. 1 to 3, the brake member 21 is attached to brake protrusions 21d and 21e that are locked to the reel hubs 4a and 4b.
The leg portions 2 are vertically disposed on both sides of the plate-like portion 21a.
1b and 21c are pre-aligned slightly outward so that the distance A between the outer edges of their lower ends is slightly larger than the distance B between the outer edges 12b and 13b of the grooves 12 and 13 of the lower half 3 of the cassette case 1. It is molded so that it is tilted to the side.

When assembling the brake member 21, the legs 21b and 21c are pressed inward, and the groove 1 of the lower half 3 is
2 and 13, so the leg 2
1b and 21c, the outer edges of the lower ends of the grooves 12 and 13 touch the outer edges 12 of the grooves 12 and 13, respectively, due to their elastic repulsive force.
b and 13b, and is held in a biased and pushed inward state. In this state, the lower inner edges of the legs 21b and 21c are spaced apart from the inner edges 12a and 13a of the grooves 12 and 13, respectively.

By pushing the leg portions 21b and 21c inward in this way, the plate-like portion 21a
A pushing force is applied to the central portion of the material, and the material is deformed to cancel the downward curvature that occurred during molding. Therefore, a sufficient space is secured between the plate-shaped portion 21a and the bottom surface of the lower half 3, and therefore, the plate-shaped portion 21a does not interfere with the tape 6 wound around the reel hubs 4a and 4b. Not,
This results in smooth tape running.

In this example, the grooves 12 and 13 of the lower half 3
is the leg portion 21 when the brake member 21 is engaged.
In order to prevent the outer side surfaces of b and 21c from interfering with the left and right side walls of the lower half 3, they are provided at positions slightly spaced inward from the side walls of the lower half 3.

Further, as described above, the leg portion 21 of the brake member 21
The outer parts of b and 21c are the grooves 12 of the lower half 3, respectively.
When the brake member 21 and the lower half 3 are pressed against the outer edges 12b and 13b of the brake member 21 and the lower half 3, frictional resistance is generated between the brake member 21 and the lower half 3. Since the force is extremely small compared to the force, the brake member 21 slides smoothly in conjunction with the opening/closing operation of the front cover 8 as described above, and the brake protrusions 21d and 21
The locks are engaged and disengaged from the reel hubs 4a and 4b by e.

Further, FIGS. 4 and 5 show a second embodiment of the present invention, in which convex edges 22a and 2 having a required length in the front-rear direction are provided on the outer edges of the lower ends of the legs 21b and 21c.
2b are formed respectively, and by assembling the brake member 12 so that the convex edges 22a and 22b abut against the outer edges 12b and 13b of the grooves 12 and 13, the convex edges 22a and The leg portions 21b and 21c are pushed inward by the protrusion of the plate portion 22b, and the inward warpage of the plate portion 21a is canceled as in the first embodiment described above.

Furthermore, FIG. 6 shows a third embodiment of the present invention, in which the legs 21b and 21c of the brake member 21 are
, the distance A between the outer surfaces of the groove 12 of the lower half 3
and the distance B between the outer edges 12b and 13b of 13
By forming the leg portion 2 to be equal to
The outer edges of the lower ends of the grooves 1b and 21c are brought into contact with the outer edges 12b and 13b of the grooves 12 and 13, respectively. In this case, even if the plate portion 21a is slightly warped, the leg portions 21b and 2
Since 1c does not spread outward, the plate-shaped portion 21
a is not bent any further downward, and therefore this plate-shaped portion 21a does not interfere with the tape 6 wound around the reel hubs 4a and 4b, so the tape 6 can be smoothly rolled without any hindrance. It will be run on

In this third embodiment as well, the grooves 12 and 13 of the lower half 3 are provided spaced inwardly from the side wall of the lower half 3, as in the first embodiment described above. Leg portion 21b of brake member 21
and 21c so as not to interfere with the side wall of the lower half 3.

[Effect of idea]

As described above, in the tape cassette of the present invention, by biasing the outer side of the leg portion of the brake member toward the outer edge of the groove, inward warpage of the plate portion is canceled, so that the brake member can be wound around the reel hub. There is no interference with the tape being rotated, so the tape runs smoothly, and the inner side of the brake member's leg is separated from the inner edge of the groove, reducing friction loss against the lower half. Since there is less friction, the reel hub can slide smoothly, and the reel hub can be reliably engaged and disengaged.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional front view of the first embodiment of the tape cassette of the present invention, FIG. 2 is a perspective view of the brake member, and FIG. 4 is a longitudinal sectional front view of the second embodiment of the tape cassette of the present invention, FIG. 5 is a partially cutaway perspective view of the brake member, and FIG. 6 is the tape of the present invention. 7 is a perspective view of a conventional tape cassette, FIG. 8 is an exploded perspective view of the same, and FIG. 9 is a plan view of the same with a portion of the lower half omitted; Figure 10 is a perspective view of the same, showing the state when stored, Figure 11 is a perspective view of the same, showing the state when in use, Figure 12 is a schematic side view for explaining Figure 10, and Figure 13 is the same. 14 is a longitudinal sectional front view of FIG. 7, and FIG. 15 is a sectional view of the brake member. In the figure, 2 is an upper half, 3 is a lower half, 4a and 4b are reel hubs, 12 and 13 are grooves, 21 is a brake member, 21a is a plate-like part, 21b and 21c
are leg portions, and 21d and 21e are protrusions.

Claims (1)

[Claims for Utility Model Registration] A brake member having a U-shaped cross section consisting of a plate-like part with a pair of protrusions that engages with the reel hub and leg parts provided on both sides of the plate-like part, in which the brake member is housed. In a tape cassette, the lower halves of the upper and lower halves are provided with a pair of grooves into which the legs of the brake members slide, and the brake members are placed in the lower halves with a gap between the outer edges of the lower ends of the legs on both sides. The brake member is formed so that the distance between the outer edges of the pair of grooves is approximately equal to or slightly larger than the distance between the outer edges of the pair of grooves, and the outer side of the leg of the brake member is biased toward the outer edge of the pair of grooves. Characteristic tape cassette.